I saw this question (rather misplaced) in the MS Office forum, so I thought answering it here.
It's simple. You don't upgrade the OS from within the OS. You boot from the Vista DVD, and than it doesn't matter at all if the OS on the hard disk has an 'hourglass over the taskbar' error or not. You run in the install-Vista-mode from the DVD, not in any mode of Windows XP.
I'm afraid, however, that you might be one of the first people around to have the 'hourglass over the taskbar' error in Windows Vista. It might well be the cause carries over. Then you must do a clean install of Windows Vista, not an upgrade of a corrupted XP.
Hope this helps.
Kees
Hi - I'm currently using Windows XP Home on a Lenovo N100 laptop (Core 2 duo, 2gig Ram). I have been getting the 'hourglass over the taskbar' issue which doesn't let me run in 'normal' mode. I've been using Safe mode with Networking to read through fixes but none have worked. I had been considering upgrading to Vista Home premium anyway, so I thought I might as well do it now (thus solving my issue at the same time).
My question is: Can I install/run the Windows Vista Home Premium Upgrade in Safe Mode?...

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